1. Technical Field
The present disclosure relates generally to a surgical device. More specifically, the present disclosure relates to a fastener applying device for simultaneously applying an array of fasteners to body tissue.
2. Background of Related Art
Surgical fastening devices for simultaneously applying an array of surgical fasteners, e.g., staples or other types of fasteners are known in the art. Such devices are used for joining body tissue such as, for example, intestinal and gastric walls with spaced parallel rows of longitudinally aligned fasteners. These surgical fastening devices reduce the time of wound closure in a surgical procedure.
Typically, these devices include a fastener holder disposed on one side of the tissue to be joined, and an anvil assembly parallel to the fastener holder on the other side of the tissue to be fastened. The fastener holder is moved linearly towards the anvil assembly so that the tissue is clamped between them. The fasteners are driven from the fastener holder so that the ends of the fasteners pass through the tissue and form finished fasteners as they make contact with the anvil assembly, thereby producing an array of finished fasteners in the tissue. The fasteners can be one or two piece and made of metal, non-absorbable polymers, or bioabsorbable polymers such as plyglycolide, polylactide, and copolymers thereof.
U.S. Pat. No. 5,137,198 to Nobis et al. ("Nobis") discloses a fastener applying device including a cartridge that is advanced towards an anvil assembly by an advancing mechanism. The advancing mechanism includes a first actuator member for advancing the cartridge towards the anvil assembly at an accelerated rate and a second actuator member spaced from the first actuator member for incrementally advancing the cartridge towards the anvil assembly.
One problem associated with such a device is that a surgeon must be able to move between and manipulate the first and second spaced actuator members while simultaneously maintaining the fastener applying device in a substantially fixed position with respect to body tissue to be repaired. This may be difficult to accomplish during the course of a surgical procedure.
Typically, fastener applying devices include a pusher bar that is advanced over a predetermined stroke to interact with and eject the fasteners from the cartridge. At least one driver is positioned within the cartridge between the distal end of the pusher bar and the fasteners such that the pusher bar advances the drivers into engagement with the fasteners. The length of the drivers may be varied to facilitate ejection of different size fasteners from a fastener applying device having a fixed pusher bar stroke.
U.S. Pat. No. 3,692,224 to Astafiev et al. describes a fastener applying device in which the driver is integrally formed with the pusher bar and not housed within the cartridge. The pusher bar is movable over a fixed stroke to eject the fasteners from the cartridge. Because the stroke of the pusher bar is fixed, only a single size fastener can be properly ejected from each fastener applying device. If a cartridge housing fasteners not sized for use with a particular fastener applying device is inserted into the fastener applying device, advancement of the pusher bar over its fixed stroke will result in either overadvancement or underadvancement of the fasteners into body tissue.
Accordingly, a need exists for an improved fastener applying device which overcomes the above-noted disadvantages, is easy to use and provides greater reliability when repairing tissue.